starting with the latest on cory monteith. How his shocking death is so hard on his co-star. Chris connelly has more on this story. &#9834; I'm forever yours faithfully &#9834; Reporter: If "glee" had a face, it belongs to cory monteith. His death at the age 31, has left so many bereft. As many relieved their grief online, there's someone whose grief is a private matter. Lea michele, monteith's co-star on "glee." And since 2012, his girlfriend. Come on, cory. Let's make this. It's nice seeing you. Reporter: What these once chose to share with the world on social media and on video, now provides a poignant chronicle, of young people who took evident delight in each other's company. The first impression I had when I met lea was, I was intimidated. Reporter: The chemistry on screen was plain to see, like in this backstage clip they enjoyed shooting. Be careful he doesn't snatch that slip cam out of your hand. Wait a second. Reporter: On twitter, she mentioned him frequently. Wishing a very happy birthday to the best guy I know. Thanks for making me feel like the luckiest girl in the world every day. That tweet coming on may 11, some two weeks after he completed a month-long stint in rehab just two months before his passing. Lea is obviously extremely devastated. She hasn't spoken publicly yet. Her rep issued a statement for her privacy to be respected. Reporter: And so, this june 8th event in los angeles, appears to be their final joint appearance. I think he looks great, doesn't he? So handsome. &#9834; It's such a shame for broken heart &#9834; Reporter: For "good morning america," chris connelly, abc news, los angeles.

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